Trivia Time: What Do the Numbers on Your Credit Card Mean?

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Have you ever wondered what the numbers on your credit card mean?  Are they a random assortment of digits, or do the numbers actually mean something?  And why does your AMEX card usually start with “3” and your Visa card usually start with “4”?

You’ve probably noticed that certain types of cards always begin with the same number.  But there’s a lot more information contained in your credit card number than you probably realized!

Trivia Time What Do The Numbers On Your Credit Card Mean
There’s More to a Credit Card Number Than Most Folks Realize!

It’s Not Just a Random Number

Most credit card issuers follow the system governed by the American National Standards Institute (ANSI).  You can get a lot of information from a card just from the numbers!

1.   First Digit on the Card

The 1st digit on the card is the Major Industry Identifier (MII).  This tells you the category of the card issuer.  For example:

  • Cards beginning with 1 or 2 are issued by airlines or other (future) industries
  • Cards beginning with 3 are travel, entertainment, or banking & financial cards (this includes American Express, some Diner’s Club cards, and Carte Blanche)
  • Cards beginning with 4 are banking & financial cards (Visa)
  • Cards beginning with 5 are banking & financial cards (includes MasterCard)
  • Cards beginning with 6 are merchandising, banking & financial cards (includes Discover)
  • Cards beginning with 7 are petroleum cards (like Exxon)
  • Cards beginning with 8 are telecommunications cards
  • Cards beginning with 9 are for national assignment
Trivia Time What Do The Numbers On Your Credit Card Mean
You Can Tell What Type of Card It Is Just From the 1st Digit

2.   First 6 Digits

You can get even more information from the 1st 6 digits on the card.  This is known as the Issuer Identification Number (IIN).  From the IIN, you can tell which bank issued the card, the country of origin, and sometimes the specific card type (for example, Visa Signature, World MasterCard, or business card).

You can find out your credit card details by going to the website and entering the 1st 6 digits of any card in the search box.  I tried it with the Chase Sapphire Preferred card and it told me:

  • The card issuer (Chase Bank)
  • The country (US)
  • The brand (Visa)
  • The card category (Visa Signature)
  • The latitude and longitude (38 degrees north and 97 degrees west) of the issuing country!
Trivia Time What Do The Numbers On Your Credit Card Mean
These 6 Digits Are Unique to the Chase Sapphire Preferred Card

This is kind of fun if you like numbers or are just obsessed with credit cards (like some of us!). 😉

I tried out the American Express Gold Delta SkyMiles card, and it knew it was an AMEX credit card:

Trivia Time What Do The Numbers On Your Credit Card Mean
It Knows the Gold Delta SkyMiles Card Is an AMEX Credit Card

And it recognized my old Chase Ink Plus card as a business elite MasterCard (although new cards are issued as Visas)!

Trivia Time What Do The Numbers On Your Credit Card Mean
It Knows the Chase Ink Plus Is a Business Elite MasterCard

Cards from foreign countries will return similar information.  For example, a Canadian American Express card looks something like this:

Trivia Time What Do The Numbers On Your Credit Card Mean
You Can Get Information on Foreign Credit Cards, Too!

I won’t admit to how much time I spent entering random 6-digit numbers beginning with 3, 4, and 5, but let’s just say there are a lot of different credit cards in the world!

3.   The Next Digits (Except the Last)

The numbers that follow the Issuer Identification Number (except the last digit) are your account number.  The length of the account number depends on the type of card.

Often, authorized users on credit card accounts will have an account number slightly different from that of the primary cardholder.  But that’s not always the case!

Trivia Time What Do The Numbers On Your Credit Card Mean
Account Numbers on Authorized User Cards Are Sometimes Slightly Different

Account numbers are random, which is probably a good thing!

4.   The Last Digit

The last digit on any credit card is a check digit or checksum, which is used to validate the credit card number.

Credit card issuers use a formula called the Luhn Algorithm to create the check digit.  But with a little math, you can use the check digit to find out if a credit card number is fake!  I’ll show you how to do this in a future post.

Bottom Line

You can learn a lot from your credit card number!  It’s not just a random sequence of digits.

The 1st digit will always tell you the type of card such as Visa or MasterCard.  And the 1st 6 digits will tell you the country, issuing bank, type of card, and sometimes even sub-category.  You can find this information online by searching on

The last digit of your credit card number is the check digit.  It’s used to validate the card.  I’ll show you how to use the check digit to find out if a card number is fake in a later post!


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